Heating furnace



y 0- A. R. MCARTHUR ET AL 1760762 HEATING FURNACE Filed Jan. 24, 1928 &Sheets-Sheet 2 May 27, 1930.

A. R. M ARTHUR ET AL HEAT ING FURNACE Filed Jan. 24, 1928' 3 Sheets-Sheet Patented May 27, 1930 UNITED' s'' '-s PA-TENT OFFICE .manun R. ucnmmm, or GARY, INIVDIANA, AND nowau a MdrLvuED, `or Me: CANDLESS TOWNSHIP, ALLEGHENY COUNTY, PENNSYLVANIA, ASSIGNORS ro, AMERICAN snnnr AND TIN ZELATE COMPANY; or' rrrsaunen, PENNSYLVANIA,

A CORPORATION OF NEW JERSEY Emr n& rUnNAcE Application filed January 24, 1928. Serial No. 249,147.

This invention relates to-heating furnaces and, while not 'limited thereto, relates more articularly to continuous heating furnaces or heating sheets and packs of sheets, and has for one of its objects the provision of a furnace of this class having a co'mbustion chamber separate from and along the one side of the heating chamber, so as to provide a chamber in which tar and soot will* deposit when burning raw producer gas.

Another object is to provide a novel form of com'bustion port between the combustion and heating chambers, and a novel form of roof over both of said chambers whereby the products of combustion will have a centrifugal force imparted to them as they pass into said heating chamber.

A further object is to provide a furnace of this class having a novel form of conveying means whereby .the sheets will be'conveyed 7 through the furnace at varying speeds at different points in the length of the furnace.

In the drawings- Figure 1 is a sectional plan of a furnace constructed in accordance with this invention.

Figure 2 is a side elevation, the right-hand half of which is sectioned on the line II--II 'of Figure 1, r

Figure 3 is a sectional side elevation taken on the line III-III of Figure 1-. 4 Figure 4 is a transverse sectional elevation taken on the line IV-IV of Figure 1.

Figura 5 is a rear end elevation.

Referring more particularly to the drawings, the numeral 2 designates the heating chamber and the numeral 3 designates the combustion chamber of 'the furnace. The

. walls of the furnace are of usualconstruction and are composed of brick with the usual steel supportingstructure X. The one-side 'wall 4 of 'the frnace is ofset horizontally, i as 'at 5, and then continued upwardly, as at 6, for the greater portion o its length to 'form the combustion chamber 3. A partition wall 7 is built up on the horizontal 'off'- set portion '5 of the side wall 4 in line with the' lower portionof said wall and serves to separate' the heating and combustion cham- The side wall 8'op`posite the side wall 4 is a strai ht, vertical wall and' is of materially less height than the wa1 l-4. Atransversely.

curved or arched roof 9 extendsfrom the top of the side wall 4 to the top of the wall 8 and has the highest point of its curve or arch products of combustion' are discharged' into i the heating chamber. The port 10 may ex- 'tend along the entirelength of the wall 7 as shown, or mayterminate short of the forward' end, as desired. i

A burner 12 is mounted in the rear end wall 14 of the furnace so as to deliver products of combu stion to the combustion chamber 3. I

The heating chamber is provided with an inlet opening or port 15'in the rear end wall 14,- and' with an outlet or-disch'arge opening or port 16 in the forward end wall 17, to provide for the inlet and discharge of the sheets, respectively. i y a A vertical flue 18 is mounted on. the outer face of the forward end wall 17 and' is adapted to receive the products of combustion'escaping through the discharge opening or port 16 of the heating chamber. 'The flue 18 has an open lower end and has its up'pe'r end connected by a conduit 19 witha stack 20.

. A preheater unit 20* is mounted in the flue not a part of the' present invention, and will be made the subject matter of a separate application for patent. Therefore, it will not be described nor shown in detail.

'A series of con'veyer rollers 22 of the disk type are'arrang ed transverselv in the heating chamber 2 andhave their shafts 23 pro j ecting through the side walls of the furnace and ournaled in bearings 24 mounted on the steel supporting structure X. A short driveshaft 26 is connected to each of the rollershafts 23 'by a flexible couplin'g 27.

is journaled suitable bearings on a stand I support 29.

` The drive-shafts 26, connected to all the roller-shafts 23 from the rear endof the furnace fo'rwardly to within a short distance' -with a pinion 35 on the armature-shaft of a drive-motor 36. The circuit to the motor 36 is adapted to be controlled by the roller to which the sheets being heated are to be delivered, and since any usual form of standard controller may be used-for this purpose, no

. illustrationis made of this element.

Inoperation, the furnace will be prefer ably fired with raw producer gas and the gas will be partly consumedt'or burned in the combustion chamber 3. The partly burned gases and. products of combustin will -pass rom the combustion chamber 3 through the port 10 into the heating chamber 2.

When raw producer gas is burned, especially when the combustion is incomplete, as is essential in the present ins'tance in order to maintain a non-oxidi-zing atmosphere in the *heating chamber 2, the burning gas will deposit tar and soot particles. The combustion chamber 3 serves to trap'the tar and soot deposits from the burning gas in the furnace .of this invention and thereby prevents the deposits of tar and soot from being deposited on the metal being'heated.

Due to the curved or arched form of the roof 9, the partly burned gases and products -of combustion, when passing from` the. combusti'on chamber 3 to the heating chamber 2,

ucts ofcombustion will pass from the com-`.

'small amount of flame to pass throughthe w inlet port .15 of the heating chamber. The v passing of this small amount .of flame through 'the`mlet port 15 is essential in order to block this sport and prevent the A u The heating chamber 2 will have a centrifugal force, imparted there-' to which, coupled with the normal forwardly projecting force produced by the -burner 12, -will cause the flame and products to assume `a fogwardly traveling swirling motion "through the heating chamber so as to pass over and under the sheets being heated.

-The major portion of-the flame and prod bustion chamber at-the rear or largest end of the port 10-`so as to cause a crowdng of the flame at this end and thereby force a ingress of cold air through the open port. u

the flame and roductsofcombustion for its entire 'length a though the 'flame willbehot' ter near the' rear' or: inlet of; the' furnace than at the forward or exit-end. By providing the hottest zone of the heating chamber 2'adjacent its rear or inlet 'end where the sheets are cold, scaling of the sheets is prevented since the cold sheets will take up the heat read'ly without scaling. v v

The flame and products of combustion will pass from the furnace through the discharge or exit port 16 and, due to the draft in the flue 18, will pass into this flue and to the stack.

When' the furnace is heated sheets or packa of sheets will be passed into the rear end of the heating chamber 2 through the inlet opening or port -15 and will be conveyed through the furnace by therollers 22.

The worm driven rollers will be rotated at a materially .slower speed than the spiral gear driven rollers at the forward end of the heating chamber, so' that ,the sheets will travel slowly through the major length of the heating chambe'r and be heated, then will be delivered with considerable speed and force from the discharge or forward end of the furnace. i

The furnace willbe under the control of the roller receiving the heated sheets and he will close the circuit to the motor 36 so as to' operate the rollers 22 when 'he-desires a. sheet or pack ofsheets only. 4

In view of this, it will be underst'ood that .the sheets will be moved with a step-by-step movement through the furnace;

It will, ofcourse, be understood that we do not wish to limit our invention to this,

step-by-step movement since the furnace may be so timed that the sheets may move con tinuously through the furnace without interruption.-.

Wh1le we have descr bed certan specfic embodments of our nvention, we do not wish to be limited thereto since various modi-` fications' may be 'made without departing from the scope of our invention,.as defined in the appended claims.

We claim- V 1. A continuous heating furnace for heating sheets and packs of sheets comprising an elongated heating chamber having an entranceport in one end and a discharge port in the other end, acombusti'on chamber along one side of said heating chamber and Vseparated therefrom for at least a part of its length by a partitionwall, an' elongatedport formed above said partition wall for at least 'a part of -itslength, said port being reduced in area from the entrance end toward the dlS- charge'end of the furnace, and a source of combustibles at theentrance end of said combustion chamber.

'willbe filled with 2. A continuous' heating furnace for beats ing sheets and packs of sheets comprising an elongated heating 'chamberhaving an en:

trance portin one' end and a discharge port in the other end, a combustionc'hamber along leo one side 'of said heating chamber and sepatibles at the end of said combustion chamber rated there-om for at least a part of its' having the greatest port area. length by a partition wall, an elongated port In testimony whereof, we have hereunto forned above 'said partition wall for at least set ou hands. Y 'a part of its length, said port being reduced in ARTHUR MCARTHUR- area from the entrance end toward the dis: HOWARD MOILVRIED- charge end of the furnace, a burner at the i entrance end of said combustion c-hamber, the products of combustion being adapted to pass i through saidelongated port into said heating 75 chamber and to travel longitudinally of said heating cbamber and escape through said discharge port, and means for conveying the sheets through said heating chamber. 3. A continuous heating furnace for heat- 80 ing sheets and packs of sheets comprising an elongated heating chamber having an entrance port in one end and a discharge port in the other end, a combustion chamber go along one side of said heating chamber and v 85 v separated therefrom for at least a part of its length by a partition wall, an' elongated port. formed above said partition wall for at least a. part ofits length, said port being reduced in area from the entrance end toward the disv 90 charge end of the furnace a burner at the entrance end of said combustion chamber. and a curved roof wall extending over both of said chambers, said wall having its highest point over'said partition wall.

4. A continuous heating furnaee for heating sheets and packs of sheets com rising an -elongated wide heating chamber aving an entranoe port inone end and a discharge port in the other end, a narrow' combustion chamber along one side of said heating chamber and' separated therefrom for at least a part of its len h by a fpartition wall, an elongated port ormed along the top of said 40 parttion wall for at least a part of its' length 105 through which the products of combustion pass into said heating chamber, said port be reduced in area from the entranoe end toward the discharge end of the furnace, a

burner at the entrance end-of said .combus- I a y o tion chamber, and a transversely `curved roof wall extendng' over both of said chambe's said wall having its highest point over said partition wall and bein adapted to impart a oentrifugal whirlto t e products of com-' eustion as they pass into sad heating Cham- 5. A continuous heating furnace comprising an elongated heating chamber having en- 55 trance and discharge ports, a comb'stion cha'nber along one side of said heating chamber and of materially shorter length thansaid heating chamber, said combustion and heating chambers being separated for at least A a part of their length by a partition wall, an

elongated port formed above said partition' wall for at least a part of the length of' said wall, said port being reduced in area" from one end toward the other end of said comi bastion lmber, and a source of comb'sj 

